1. Field of the Invention
The present invention relates generally to full-thickness resection devices (FTRDs) and methods of using such devices to perform localized resections of lesions in organs, for example, substantially tubular organs such as the colon. The present invention has particular application to transanal and transoral surgical procedures, although it is not limited thereto.
2. Description of the Related Art
Resection procedures involve excising a portion of an organ, approximating the surrounding tissue together to close up a hole created thereby, and removing any excess tissue caused by the approximation. Various conventional devices and procedures are available for resecting lesions in substantially tubular organs.
For example, several known resection devices and procedures require at least one incision in an area near the portion of the organ to be excised. The incision is required to allow the physician to access the organ section to be excised and guide the device to that section. The incision permits access to the lesion or treatment site for these resection devices which do not have sufficient steering and/or viewing capabilities to appropriately access the site without such a surgical opening thereto. Thus, when an organ section to be excised is beyond the reach of such a device, or the device is not flexible enough to wind through the organ to the site to be excised, an incision will be required to position the device for the procedure. Of course, incisions are traumatic to the patient and may involve a partial or entire loss of mobility to the patient while recuperating from the incision, in addition to recovering from the resection procedure itself. The time required to recover from such a procedure also is often longer than for procedures which do not require incisions.
One type of conventional resection procedure utilizes a circular stapling instrument in which a tubular section of a tubular organ (in other words, a length of the organ) is excised, resulting in the tubular organ being separated into first and second segments. The end sections of the first and second segments are tied closed, in for example a purse-string fashion, and stapled together. The tissue of the xe2x80x9cpurse-stringedxe2x80x9d end sections radially inside the line of staples is then cut off. In this circular anastomosis procedure, at least one separate invasive incision is typically made near the section to be excised in order to cut out the section to be removed and to purse-string the ends of the first and second sections of the organ. Also, a separate incision may be needed to place a first part of the resection device in the first segment and a corresponding second part of the device in the second segment (e.g., anvil in one segment and stapling head in the other) so that the device may bring the first and second segments together and staple them together. Thus, this type of resection procedure involves the drawbacks mentioned above in regard to procedures requiring invasive incisions as well as additional complications resulting from the removal of an entire tubular segment of the organ including, for example the risk of spillage of non-sterile bowel contents into the sterile body cavity, which can cause severe infection and possibly death.
An alternative resection device includes a stapling and cutting assembly on a shaft which can be bent or formed into a desired shape and then inserted into a patient""s body cavity. Once the shaft has been bent into the desired shape, the rigidity of the shaft ensures that that shape is maintained throughout the operation. This arrangement limits the effective operating range of the device as the bending of the shaft into the desired shape before insertion and the rigidity of the shaft once bent require the physician to ascertain the location of the organ section to be removed before insertion, and deform the shaft accordingly. Furthermore, the rigidity of the shaft makes it difficult to reach remote areas, particularly those areas which must be reached by a winding and/or circuitous route (e.g., the sigmoid colon). Thus, an incision may be required near the organ section to be excised in order to position the device at that organ section.
Furthermore, devices have been described in U.S. Pat. Nos. 6,119,913 and 6,126,058 including resectioning means guided through the colon using a flexible endoscope. Although these devices describe the removal of lesions beyond the splenic flexure of the colon, removals in these locations are limited to pendunculated-type polyps a stem of which may be severed by a snare or very small polyp-type tumors that can be removed using what are essentially biopsy devices (limited to mucosal depth only).
To help describe this, FIG. 1 shows the general shape of a portion of a colon 10 up to the cecum. The colon 10 has the following main sections: the rectum 11, the sigmoid colon 12, the descending colon 13, the splenic flexure 14, the transverse colon 15, the hepatic flexure 16, the ascending colon 17, and the cecum 18. The small bowel 19, or ilium, connects to the cecum 18, as shown in FIG. 1. Prior art resection devices purport to navigate the colon 10 up to the splenic flexure 14, but no further due to the right angle turn at the splenic flexure. Turns within the sigmoid colon 12 are described as being navigated and straightened by current endoscopy techniques allowing these devices to travel past the sigmoid colon 12. However, existing resection devices, which do not have steering capability or sufficient flexibility, must be pushed along the colon and rely on the colon wall to guide them. Pushing beyond the splenic flexure 14 significantly increases the risk of damaging the colon by, for example, tearing its wall. Thus, lesions beyond the splenic flexure that cannot be removed with a simple biopsy device are typically removed by open or laparoscopic surgery. To do so, a colonoscope is inserted in the rectum and guided to the section of the colon where the lesion is located. That section of the colon then is marked with a dye so the surgeon may determine what tissue is to be removed during surgery.
The present invention is directed to a resection head for endoscopic resection of tissue comprising an endoscope receiving channel extending therethrough so that an endoscope may be slidably received therein and a first position adjusting mechanism for moving the resection head relative to an endoscope received in the endoscope receiving channel between a first retracted position in which a distal end of the endoscope extends beyond a distal end of the resection head and a deployed position in which the distal end of the endoscope is received within the endoscope receiving channel. The resection head also comprises a resection chamber within an outer wall of the resection head, at least a first portion of the outer wall being moveable with respect to a second portion thereof to open the resection chamber to an exterior of the resection head and a resection mechanism for resecting tissue received within the resection chamber.
The present invention is also directed to a method of resecting tissue comprising the steps of coupling a distal end of a flexible guide to a desired location on a wall of a body lumen and sliding a resection head coupled to an endoscope over the guide to the desired location, wherein the resection head is coupled to an endoscope with the flexible guide extending outside of the endoscope between an entrance to the body lumen and the desired location. A selected portion of tissue to be resected is then drawn into a resection area of the resection head and resected.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.